Income Taxes (Effective Income Tax Rate Reconciliation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Taxes computed at statutory rate, amount	$ 102,927	$ 138,431	$ 119,292
State income taxes, net of federal income tax benefit, amount	10,323	13,272	9,048
Tax-exempt interest, amount	(8,755)	(8,612)	(9,100)
Life insurance contracts, amount	(4,020)	(1,812)	(2,653)
Tax credits, amount	(9,443)	(8,039)	(7,889)
Employee share-based compensation, amount	(505)	(2,084)	(1,671)
FDIC assessment disallowance, amount	2,893	1,836	1,609
Net operating loss carryback under CARES act, amount		238	(4,948)
Other, net, amount	4,106	1,877	1,153
Total expense included in net income	$ 97,526	$ 135,107	$ 104,841
Taxes computed at statutory rate	21.00%	21.00%	21.00%
State income taxes, net of federal income tax benefit	2.10%	2.00%	1.60%
Tax-exempt interest	(1.80%)	(1.30%)	(1.60%)
Life insurance contracts	(0.80%)	(0.30%)	(0.50%)
Tax credits	(1.90%)	(1.20%)	(1.40%)
Employee share-based compensation	(0.10%)	(0.30%)	(0.30%)
FDIC assessment disallowance	0.60%	0.30%	0.30%
Net operating loss carryback under CARES act			(0.90%)
Other, net	0.80%	0.30%	0.30%
Income tax expense	19.90%	20.50%	18.50%